1. Departament of Otorhinolaryngology; University Hospital of Santiago de Compostela; Santiago de Compostela Spain
2. María Jose Jove Foundation; A Coruña Spain
3. Clinical Epidemiology and Biostatistics Unit; University Hospital Complex; A Coruña Spain
4. Spanish Biomedical Research Networking Centre-CIBERES; Madrid Spain
5. Department of Respiratory Medicine; Hospital Universitari Vall d'Hebron; Barcelona Spain
6. Departament of Pediatrics; Servicio Galego de Saúde; A Coruña Spain
7. Grupo de investigación Cardiovascular (GRINCAR); Instituto de Investigación Biomédica de A Coruña (INIBIC); Instituto Universitario de Ciencias de la Salud; Universidade da Coruña; A Coruña Spain
8. Department of Medicine; University of Santiago de Compostela; Santiago de Compostela Spain
9. Department of Respiratory Medicine; University Hospital of Santiago de Compostela; Santiago de Compostela Spain
10. Health Research Institute of Santiago de Compostela (IDIS); Santiago de Compostela Spain